MDEV-20867 - Perform careful review of "Server crashes with BACKUP STAGE and FLUSH TABLE table_name"

Reverted original patch (c2e0a0b).

For consistency with "LOCK TABLE <table_name> READ" and "FLUSH TABLES
WITH READ LOCK", which are forbidden under "BACKUP STAGE", forbid "FLUSH
TABLE <table_name> FOR EXPORT" and "FLUSH TABLE <table_name> WITH READ
LOCK" as well.

It'd allow consistent fixes for problems like MDEV-18643.

1 files changed, 3 insertions, 24 deletions

diff --git a/mysql-test/main/backup_interaction.test b/mysql-test/main/backup_interaction.test
index 8ac905cc6ff..09ed769c898 100644
--- a/mysql-test/main/backup_interaction.test
+++ b/mysql-test/main/backup_interaction.test
@@ -509,30 +509,9 @@ BACKUP STAGE END;
 
 CREATE OR REPLACE TABLE t1 (pk INT PRIMARY KEY, f INT);
 BACKUP STAGE START;
+--error ER_BACKUP_LOCK_IS_ACTIVE
 FLUSH TABLE t1 FOR EXPORT;
-UNLOCK TABLES;
-BACKUP STAGE END;
-DROP TABLE t1;
-
-CREATE TABLE t1 (a INT);
-BACKUP STAGE START;
-FLUSH TABLE t1 FOR EXPORT;
-UNLOCK TABLES;
---connect (con1,localhost,root,,test)
---send BACKUP STAGE START
---connection default
-BACKUP STAGE END;
---connection con1
-reap;
-BACKUP STAGE END;
---disconnect con1
---connection default
-DROP TABLE t1;
-
-CREATE TABLE t1 (a INT);
-BACKUP STAGE START;
-FLUSH TABLES t1 WITH READ LOCK;
-UNLOCK TABLES;
-BACKUP STAGE BLOCK_COMMIT;
+--error ER_BACKUP_LOCK_IS_ACTIVE
+FLUSH TABLE t1 WITH READ LOCK;
 BACKUP STAGE END;
 DROP TABLE t1;